Hinged closure for plastic containers



Nov. 3, 1964 P. 1-. SCHURMAN ETAL 3, 5,

HINGED CLOSURE FOR PLASTIC CONTAINERS Filed Feb. 13, 1963 INVENTORS PETER T. SCHURMAN RAYMOND c. CONFER ATTORNEYS United States Patent 3,155 269 HINGED CLOSURE FORPLASTIC CONTAINERS Peter T. Schurman, Snyder, and Raymond C. Confer, Gasport, N.Y., assignors to Airmold Plastics, Inc, Tonawanda, N .Y.

Filed Feb. 13, 1963, Ser. No. 258,203 Claims. (Cl. 220-31) This invention relates to a new and useful hinged closure for plastic containers.

The primary object of our invention is to provide a durable hinge, simple in construction, integral with a container of thermoplastic material and having a well defined hinge action.

Another object of our invention is to provide a hinge, as aforesaid, together with means for precisely alining the closure with the hinge where the closure does not have a fixed positioning seat on the container.

In one form thereof, a hinged closure constructed in accordance with our invention is characterized by the provision of a container of thermoplastic material, the container having a side wall severed at laterally spaced points from one end of the container toward the other to provide a hinge leaf, the hinge leaf being joined to the container by a groove of reduced wall thickness to provide a hinge axis, and a closure of thermoplastic material secured to the hinge leaf for opening and closing movement about the hinge axis.

The foregoing and other objects, advantages and characterizing features of our invention will become clearly apparent from the ensuing detailed description of a presently contemplated, illustrative embodiment thereof, considered in conjunction with the accompanying drawing illustrating the same wherein like reference numerals denote like parts throughout and wherein:

FIG. 1 is a front perspective view of a plastic container and hinged closure of our invention, shown in open condition;

FIG. 2 is a fragmentary, rear perspective view, on an enlarged scale, of the container rear side wall, the closure being omitted to better show the hinge leaf;

FIG. 3 is a further enlarged, fragmentary, transverse sectional view thereof, taken about on line 3-3 of FIG. 2; and

FIG. 4 is a fragmentary, exploded, front perspective view of the container and closure, on the same scale as FIG. 2, showing locating means on the container hinge leaf and the closure for alinement thereof during assembly.

In the illustrated embodiment, the closure hinge of our invention is provided as an integral part of a container of thermoplastic material, such as high density polyethylene, polypropylene, polyvinyl and elastomeric polyolefin. It mounts a closure, which can be formed of any of these materials. Since the closure need not flex, it also can be made of materials such as polystyrene. Preferably, the closure material is bondable or weldable to the container material, as will more clearly appear.

Referring now in detail to the accompanying drawing, there is shown a container 1, of open top, box-like construction, adapted to be closed by a closure or cover 2. Container 1 has a rear wall 3, to which cover 2 is hinged, and a ledge or shoulder 4 extends around container 1. Shoulder 4 is spaced below the open top of the container, leaving a neck or rim 5 over which the cover skirt 6 telescopes as it seats upon the shoulder 4.

Cover 2 can be provided with a bail type handle having pivot ends 7 extending through apertures in the cover, and container 1 can include a latch 8 adapted to cam into cover slot 9 and project therethrough to releasably hold the cover in closed position.

3,155,269 Patented Nov. 3, 1964 This invention is concerned with the hinge securing the cover 2 on container 1, which hinge is constructed as follows.

The rear Wall 3 of the container 1 is severed, at laterally spaced points thereacross, along the lines 10, 10 (FIG. 2). These lines of severing extend from the open upper end of container 1 completely down the upstanding rim 5 to shoulder 4, and then completely across the shoulder 4. This defines and provides a hinge flap or leaf 11 integral with container 1 and consisting of the severed portion 5' of rim 5 and the severed portion 4 of shoulder 4.

The rear wall of cover skirt 6 is-secured to hinge leaf 11 with its bottom edge seating against the hinge shoulder portion 4', and with the cover skirt 6 secured flat against the hinge leaf rim portion 5, preferably by bonding although other types of fastening can be used.

Further in accordance with our invention, hinge leaf 11 does not merely curve and bend, but is provided with a definite hinge axis. This is accomplished by grooving the container along the line of juncture between hinge leaf 11 and container rear wall 3 and providing a reduced wall thickness at this point. Preferably, the container is notched, as shown at 12, to an apex 13 of reduced thickness.

This attenuated, grooved juncture provides a clearly defined hinge point, which ideally is at apex 13 and will be located in the region of the notch 12, although its position seems to depend upon and perhaps can be controlled by the shape of the notch and the thickness of the material.

In any event, such grooving and reduction in wall thickness provides a clearly defined hinge line.

In addition to the desirable hinge action thus provided, this also strengthens the hinge. This is because flexing such thermoplastic material at a given point produces a molecular alinement which strengthens the material, through the first part of the hinge life.

Where the container is provided with a fixed positioning means for the cover, such as shoulder 4 upon which cover 2 seats, the cover position is defined and proper location of the cover on the hinge leaf, for assembly, is readily determined by positioning the cover on the container. However, where there is no such locating shoulder, the proper positioning of the cover on the hinge is more difiicult, and locating means such as indicated in FIG. 4 can be provided.

Thus, the cover skirt 6 can be provided with a pair of detents 14, integral therewith and precisely positioned thereon. Detents 14 are adapted to extend through openings 15 which are precisely located in the hinge leaf 11. To assemble, the cover is brought into position with detents 14 extending through openings 15, and the abutting cover and hinge parts are bonded together. If desired, the detents can be provided on the hinge leaf, and the apertures in the cover skirt.

The illustrated container is blow molded, with notch 12 being blown outwardly, beyond shoulder 4, to apex 13 to provide the attenuated juncture. Also, it is contemplated that, where the locating means are provided, they will be molded into the container and cover parts, whereby the location thereof can be precisely determined in the molding dies. While the illustrated arrangement is considered to be preferred, under some circumstances the hinge leaf and grooved juncture could be provided on the cover, and the container bonded to the hinge.

While we have disclosed and described in detail only one embodiment of our invention, that has been done for purposes of illustration only and not by way of limitation. Such variations and modifications as will naturally occur to those skilled in the art are intended to be included within the scope of the appended claims.

Having fully disclosed and completely described our invention, and its mode of operation, what we claim as new is:

l. A hinged closure for containers comprising, a container part, a closure part, at least one of said parts being made of thermoplastic material, a side wall of said one part being severed at spaced points from one end toward the opposite end thereof to provide a hinge leaf, said hinge leaf being joined to said one part by a grooved portion of reduced wall thickness to provide a hinge axis, the other of said parts being secured to said hinge leaf for movement about said axis relative to said one part.

2. A hinged closure for containers as set forth in claim 1, wherein both said parts are made of thermoplastic material, and wherein said hinge leaf and said other part have interengaging positioning means, said last-named means including a locating detent and an aperture receiving the same.

3. A hinged closure as set forth in claim 1, wherein one of said hinge leaf and said other part is formed to provide a locating detent and the other thereof is apertured to receive the same.

4. A hinged closure for containers comprising, a container of thermoplastic material having a shoulder therearound in spaced relation to one end thereof, a side wall of said container being severed at spaced points from said one end of said container to said shoulder and across said shoulder to provide a hinge leaf, the juncture between said hinge leaf and said container being grooved and of reduced wall thickness to provide a hinge axis, and a closure of thermoplastic material seating on said shoulder and secured to said hinge leaf for opening and closing about said axis.

5. A hinged closure as set forth in claim 4, said container being notched at said grooved juncture to an apex of reduced thickness extending outwardly beyond the said shoulder.

References Cited in the file of this patent UNITED STATES PATENTS 2,938,966 Spence May 31, 1960 3,106,602 Hartz Oct. 8, 1963 THERON E. CONDON, Primary Examiner, 

1. A HINGED CLOSURE FOR CONTAINER COMPRISING, A CONTAINER PART, A CLOSURE PART, AT LEAST ONE OF SAID PARTS BEING MADE OF THERMOPLASTIC MATERIAL, A SIDE WALL OF SAID ONE PART BEING SEVERED AT SPACED POINTS FROM ONE END TOWARD THE OPPOSITE END THEREOF TO PROVIDE A HINGE LEAF, SAID HINGE LEAF BEING JOINED TO SAID ONE PART BY A GROOVED PORTION OF REDUCED WALL THICKNESS TO PROVIDE A HINGE AXIS, THE OTHER OF SAID PARTS BEING SECURED TO SAID HINGE LEAF FOR MOVEMENT ABOUT SAID AXIS RELATIVE TO SAID ONE PART. 